When I turned 21, my dad wrote me a letter, a serious missive discussing the changes this meant, both legal and in terms of how the world will deal with me. It was encouraging and the pride was clear with every word.When Kate turned 21, I wrote something similar to her.Today, Robbie’s 21st birthday, I am denied the opportunity.He was on his way to becoming a fully legal adult but he was also on his way to becoming the adult he wanted to be, a process shaped immeasurably by his disease. I wanted to see that adult, cheer him on as he completed college and headed out into the wide world, a Child Life Specialist, helping others. His heart was always generous and by finding a career where he could use that gentility to be of service would have seen him go far.Robbie wanted to marry and actually craved the white picket fence suburban dream, complete with wife and kids. Of course, he still wanted to attend cons, getting more involved with the Baltimore-based shows and be an active committee member. Most important, though, was his desire to be near Kate. He saw how important it was for Deb to have siblings near by and he wanted to make certain they would be there for each other.His goals were good, attainable ones and I would have applauded them in the letter I will never write.We’ll honor his memory with a visit to his gravesite and the go have dinner at Pizzeria Uno, his official hangout and last place of employment. We’ll eat and silently hoist our glasses and wish him a happy birthday.